Building Emissions Saving Ordinance (BESO)

The Building Emissions Saving Ordinance (BESO) requires building owners and homeowners to complete and publicly report comprehensive energy assessments to uncover energy and greenhouse gas emissions saving opportunities.

The assessments are conducted by registered energy assessors who provide tailored recommendations on how to save energy, eliminate fossil fuels, and link building owners to incentive programs for energy efficiency and electrification upgrades.

For small residential buildings with one or two units, BESO also requires homeowners to complete resilience upgrades to decrease greenhouse gas emissions and improve resilience.

BESO Requirements vary depending on the building type and size:

• 1-2 unit homes require:
  • an energy assessment at time of listing (if listed for sale before January 1, 2026)
  • an energy assessment at time of listing and resilience upgrades within 2 years of sale (if listed for sale on or after January 1, 2026)
• Up to 14,999 square foot multifamily (3+ units) and commercial buildings require an energy assessment at time of listing
• 15,000 - 24,999 square foot multifamily and commercial buildings require an energy assessment at time of listing and annual benchmarking
• 25,000 square foot or greater multifamily and commercial buildings require an assessment every 5 years and annual benchmarking